I am trying the following and it looks like it may be working, but I am not certain what the end product would be.

Basic electrolysis setup: two cups distilled water, with 3 g of copper wire on anode, and large graphite cathode, connected to 9 V, 1.5 A power supply.

I then added the following to the water:

  • 45 g of pure aspirin (acetylsalicylic acid).
  • 30 g of baking soda (sodium bicarbonate).

It has been running now for about three hours, the solution is a bright sky blue, the copper wire is about 40% dissolved. I do not know chemistry but assume that I am making several reactions form in this solution: copper carbonate, copper hydroxide, and sodium salicylate. I am not clear if the electrolysis process of these will produce a final product where all of the available copper has bonded to all the salicylate.

I would greatly appreciate an answer on what it is you think the end solution will be once the copper has fully dissolved.


Why are you using this methodology?

Copper salycilate is an insoluble salt in water, so if you put copper sulphate in water and mix this solution with salycilic acid the copper salycilate will precipitate.

If you do not have some copper sulphate it's more easy to make copper sulphate using copper wires, sulphuric acid and electrolisys (see Nurdrage video https://www.youtube.com/watch?v=arlYPz3EP7A).

Finally, in your experiment if the copper is reduced it's possible that the salicylic acid is being oxidized and therefore you do not get the desired product.

  • $\begingroup$ I was inspired by this: edu.utsunomiya-u.ac.jp/chem/v11n2/PerezBenitez/… $\endgroup$ – ol_matty_man Jun 30 '18 at 0:32
  • $\begingroup$ These were the only ingredients I had available, that is why I used the above methodology. Except I used distilled water. When I started with just aspirin water and copper the reaction was moving very slowly, about 2 hours in I saw only a few blue crystals and the copper wire had very few blue specks on it - still looked like a new copper wire, I thought perhaps it would react faster with some baking soda. I added baking soda and within minutes I had a nice deep blue reaction... Maybe because of distilled water the reaction was slow, they used tap water in the paper I linked... $\endgroup$ – ol_matty_man Jun 30 '18 at 0:44
  • $\begingroup$ I think that what I did worked, however I think it makes more sense to do the baking soda and copper reaction first with electrolysis, and then mix the aspirin in secondly without any electrolysis. I think I used way more baking soda and aspirin than was needed because of trying to do all reactions all at once. $\endgroup$ – ol_matty_man Jun 30 '18 at 1:33
  • $\begingroup$ The baking soda (NaHCO3) is not only an electrolyte but it is also required to remove (saponify) the acetyl group from acetylsalicylic acid (aspirin). $\endgroup$ – user55119 Jul 30 '18 at 2:35

You don't get a precipitate if you add coppper(II) sulfate to hot salicylic acid. It becomes a clear dark green liquid. I assume the low pH because of the addition of the sulfate ion causes the formation of an acidic complex. I added some bicarb and the copper salicylate formed a light green powder. I added enough till it stopped effervescing as I don't have a problem of carbonate contamination. I have never got crystals of copper salicylate; always powder.


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